pgsql: When implementing a coercion to a domain type with a combined

Log Message:
-----------
When implementing a coercion to a domain type with a combined
type-and-length coercion function, make sure that the coercion function
is told the correct typmod. Fixes Kris Jurka's example of a domain
over bit(N).

Modified Files:
--------------
pgsql/src/backend/commands:
copy.c (r1.233 -> r1.234)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/copy.c.diff?r1=1.233&r2=1.234)
pgsql/src/backend/optimizer/prep:
preptlist.c (r1.70 -> r1.71)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/prep/preptlist.c.diff?r1=1.70&r2=1.71)
pgsql/src/backend/parser:
parse_coerce.c (r2.123 -> r2.124)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/parser/parse_coerce.c.diff?r1=2.123&r2=2.124)
pgsql/src/backend/rewrite:
rewriteHandler.c (r1.144 -> r1.145)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/rewrite/rewriteHandler.c.diff?r1=1.144&r2=1.145)
pgsql/src/include/parser:
parse_coerce.h (r1.58 -> r1.59)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/parser/parse_coerce.h.diff?r1=1.58&r2=1.59)